1220500121 has 2 divisors, whose sum is σ = 1220500122. Its totient is φ = 1220500120.

The previous prime is 1220500109. The next prime is 1220500189. The reversal of 1220500121 is 1210050221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1036518025 + 183982096 = 32195^2 + 13564^2 .

It is an emirp because it is prime and its reverse (1210050221) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1220500121 is a prime.

It is a super-2 number, since 2×1220500121² = 2979241090722029282, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1220500096 and 1220500105.

It is not a weakly prime, because it can be changed into another prime (1220502121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610250060 + 610250061.

It is an arithmetic number, because the mean of its divisors is an integer number (610250061).

Almost surely, 2^1220500121 is an apocalyptic number.

It is an amenable number.

1220500121 is a deficient number, since it is larger than the sum of its proper divisors (1).

1220500121 is an equidigital number, since it uses as much as digits as its factorization.

1220500121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40, while the sum is 14.

The square root of 1220500121 is about 34935.6568708819. The cubic root of 1220500121 is about 1068.6757195345.

Adding to 1220500121 its reverse (1210050221), we get a palindrome (2430550342).

The spelling of 1220500121 in words is "one billion, two hundred twenty million, five hundred thousand, one hundred twenty-one".